4He dose- and track-averaged linear energy transfer: Monte Carlo algorithms and experimental verification.

Objective.In the present hadrontherapy scenario, there is a growing interest in exploring the capabilities of different ion species other than protons and carbons. The possibility of using different ions paves the way for new radiotherapy approaches, such as the multi-ions treatment, where radiation could vary according to target volume, shape, depth and histologic characteristics of the tumor. For these reasons, in this paper, the study and understanding of biological-relevant quantities was extended for the case of4He ion.Approach.Geant4 Monte Carlo based algorithms for dose- and track-averaged LET (Linear Energy Transfer) calculations, were validated for4He ions and for the case of a mixed field characterised by the presence of secondary ions from both target and projectile fragmentation. The simulated dose and track averaged LETs were compared with the corresponding dose and frequency mean values of the lineal energy,yD¯andy¯F, derived from experimental microdosimetric spectra. Two microdosimetric experimental campaigns were carried out at the Italian eye proton therapy facility of the Laboratori Nazionali del Sud of Istituto Nazionale di Fisica Nucleare (INFN-LNS, Catania, I) using two different microdosimeters: the MicroPlus probe and the nano-TEPC (Tissue Equivalent Proportional Counter).Main results.A good agreement ofL¯dTotalandL¯tTotalwithy¯Dandy¯Texperimentally measured with both microdosimetric detectors MicroPlus and nano-TEPC in two configurations: full energy and modulated4He ion beam, was found.Significance.The results of this study certify the use of a very effective tool for the precise calculation of LET, given by a Monte Carlo approach which has the advantage of allowing detailed simulation and tracking of nuclear interactions, even in complex clinical scenarios.

Pectus excavatum and mechanical chest compression of a dangerous bond.

Pectus excavatum (PE) is a malformation of the chest characterized by a median depression of the sternum. The incidence of PE is between 0.1% and 0.8%. In the last decade mechanical chest compression devices (MCCD) became of particular interest in cardiopulmonary resuscitation. Different devices became available and this resulted in an increase in their use during CPR mainly for practical reasons. Despite their increasing use, little evidence existed for their effectiveness and little was known about complications. Skin lesions and fractures of sternum or ribs are the ones with the highest incidence. Whereas subdiaphragmatic lesions, in particular fatal liver injuries are uncommon and described only in few case reports. In a recent retrospective study, CT was used to determine the proper compression landmark and depth of cardiopulmonary resuscitation in PE patients. The authors showed that the mean Haller Index in PE patients was higher than in controls, thus exposing internal organs to a higher injury risk during standard CPR maneuvers. We report the first case, to our knowledge, of liver injury during mechanical CPR in a patient with PE. Awareness is being raised on tailoring mechanical CPR in patients with chest deformities. Further exploration is needed to determine if there is a strong correlation between mechanical CPR and organ damage in PE. We believe that this case highlights the importance of individualizing CPR techniques.

Identification of mutations in the PARK2 gene in Serbian patients with Parkinson's disease.

Mutations in the PARK2 (PRKN) gene are the most common cause of autosomal-recessive (AR) juvenile parkinsonism and young-onset Parkinson's disease (YOPD). >100 different variants have been reported, including point mutations, small indels and single or multiple exon copy number variations. Mutation screening of PARK2 was performed in 225 Serbian PD patients (143 males and 82 females) with disease onset before 50 years and/or positive family history with apparent AR inheritance. All coding regions and their flanking intronic sequences were amplified and directly sequenced. Whole exon multiplications or deletions were detected using Multiple Ligation Probe Amplification (MLPA) method. We identified 12 PD patients with PARK2 mutations (5.3%). Five patients (2.2%) had biallelic mutations and seven (3.1%) were single mutation carriers. Patients with compound heterozygous mutations had earlier onset of the disease compared to non-carriers (p = 0.005) or heterozygotes (p = 0.001). Other clinical features in mutation carriers were not different compared to non-carriers. In our cohort, sequence and dosage variants were equally represented in patients, inducing their first symptoms mainly before the age of 30. For efficient genetic testing strategy, patients with early, especially juvenile onset of PD were strong candidates for both dosage and sequence variants screening of PARK2 gene.

Track structure modeling in liquid water: A review of the Geant4-DNA very low energy extension of the Geant4 Monte Carlo simulation toolkit.

Understanding the fundamental mechanisms involved in the induction of biological damage by ionizing radiation remains a major challenge of today's radiobiology research. The Monte Carlo simulation of physical, physicochemical and chemical processes involved may provide a powerful tool for the simulation of early damage induction. The Geant4-DNA extension of the general purpose Monte Carlo Geant4 simulation toolkit aims to provide the scientific community with an open source access platform for the mechanistic simulation of such early damage. This paper presents the most recent review of the Geant4-DNA extension, as available to Geant4 users since June 2015 (release 10.2 Beta). In particular, the review includes the description of new physical models for the description of electron elastic and inelastic interactions in liquid water, as well as new examples dedicated to the simulation of physicochemical and chemical stages of water radiolysis. Several implementations of geometrical models of biological targets are presented as well, and the list of Geant4-DNA examples is described.

Expression of miR-200c in claudin-low breast cancer alters stem cell functionality, enhances chemosensitivity and reduces metastatic potential.

Claudin-low tumors are a highly aggressive breast cancer subtype with no targeted treatments and a clinically documented resistance to chemotherapy. They are significantly enriched in cancer stem cells (CSCs), which makes claudin-low tumor models particularly attractive for studying CSC behavior and developing novel approaches to minimize CSC therapy resistance. One proposed mechanism by which CSCs arise is via an epithelial-mesenchymal transition (EMT), and reversal of this process may provide a potential therapeutic approach for increasing tumor chemosensitivity. Therefore, we investigated the role of known EMT regulators, miR-200 family of microRNAs in controlling the epithelial state, stem-like properties and therapeutic response in an in vivo primary, syngeneic p53(null) claudin-low tumor model that is normally deficient in miR-200 expression. Using an inducible lentiviral approach, we expressed the miR-200c cluster in this model and found that it changed the epithelial state, and consequently, impeded CSC behavior in these mesenchymal tumors. Moreover, these state changes were accompanied by a decrease in proliferation and an increase in the differentiation status. miR-200c expression also forced a significant reorganization of tumor architecture, affecting important cellular processes involved in cell-cell contact, cell adhesion and motility. Accordingly, induced miR200c expression significantly enhanced the chemosensitivity and decreased the metastatic potential of this p53(null) claudin-low tumor model. Collectively, our data suggest that miR-200c expression in claudin-low tumors offers a potential therapeutic application to disrupt the EMT program on multiple fronts in this mesenchymal tumor subtype, by altering tumor growth, chemosensitivity and metastatic potential in vivo.

A Monte Carlo study for the calculation of the average linear energy transfer (LET) distributions for a clinical proton beam line and a radiobiological carbon ion beam line.

Fluence, depth absorbed dose and linear energy transfer (LET) distributions of proton and carbon ion beams have been investigated using the Monte Carlo code Geant4 (GEometry ANd Tracking). An open source application was developed with the aim to simulate two typical transport beam lines, one used for ocular therapy and cell irradiations with protons and the other for cell irradiations with carbon ions. This tool allows evaluation of the primary and total dose averaged LET and predict their spatial distribution in voxelized or sliced geometries. In order to reproduce the LET distributions in a realistic way, and also the secondary particles' contributions due to nuclear interactions were considered in the computations. Pristine and spread-out Bragg peaks were taken into account both for proton and carbon ion beams, with the maximum energy of 62 MeV/n. Depth dose distributions were compared with experimental data, showing good agreement. Primary and total LET distributions were analysed in order to study the influence of contributions of secondary particles in regions at different depths. A non-negligible influence of high-LET components was found in the entrance channel for proton beams, determining the total dose averaged LET by the factor 3 higher than the primary one. A completely different situation was obtained for carbon ions. In this case, secondary particles mainly contributed in the tail that is after the peak. The results showed how the weight of light and heavy secondary ions can considerably influence the computation of LET depth distributions. This has an important role in the interpretation of results coming from radiobiological experiments and, therefore, in hadron treatment planning procedures.

Construction and functional analysis of novel dominant-negative mutant of human SOX18 protein.

SOX18 transcription factor plays important roles in a range of biological processes such as vasculogenesis, hair follicle development, lymphangiogenesis, atherosclerosis, and angiogenesis. In this paper we present the generation of a novel SOX18 dominant-negative mutant (SOX18DN) encoding truncated SOX18 protein that lacks a trans-activation domain. We show that both wild-type SOX18 (SOX18wt) and truncated human SOX18 proteins are able to bind to their consensus sequence in vitro. Functional analysis confirmed that SOX18wt has potent trans-activation properties, while SOX18DN displays dominant-negative effect. We believe that these SOX18wt and SOX18DN expression constructs could be successfully used for further characterization of the function of this protein.

Are irreversible morphological [corrected] signs of portal hypertension in neurological form of Wilson's disease associated with treatment delay? A pilot study.

Aim of this study was to evaluate the rate of morphological liver and spleen abnormalities in patients with neurological clinical presentation of Wilson's disease (WD). Fourteen patients with neurological presentation of WD divided into group A (5 patients who initiated chelating therapy <24 months from the first symptoms) and group B (9 patients whose therapy started ≥24 months after the initial symptoms) underwent abdominal MRI examination. Abnormal findings on abdominal MRI were present in 28% of patients with neurological form of WD. Significant hepatosplenomegaly was present in none of the patients from group A and in 4 (44%) patients from group B. In addition, macronodular liver cirrhosis and peritoneal effusion were evident in two and one patient from group B, respectively, and in none of the patients from group A. Our results suggest that severe portal hypertension and liver damage in patients with neurological presentation of WD might be reversible or do not even develop if chelating treatment is initiated <2 years after the onset of symptoms.

BPC 157 therapy to detriment sphincters failure-esophagitis-pancreatitis in rat and acute pancreatitis patients low sphincters pressure.

Possibly, acute esophagitis and pancreatitis cause each other, and we focused on sphincteric failure as the common causative key able to induce either esophagitis and acute pancreatitis or both of them, and thereby investigate the presence of a common therapy nominator. This may be an anti-ulcer pentadecapeptide BPC 157 (tested for inflammatory bowel disease, wound treatment) affecting esophagitis, lower esophageal and pyloric sphincters failure and acute pancreatitis (10 µg/kg, 10 ng/kg intraperitoneally or in drinking water). The esophagitis-sphincter failure procedure (i.e., insertion of the tubes into the sphincters, lower esophageal and pyloric) and acute pancreatitis procedure (i.e., bile duct ligation) were combined in rats. Esophageal manometry was done in acute pancreatitis patients. In rats acute pancreatitis procedure produced also esophagitis and both sphincter failure, decreased pressure 24 h post-surgery. Furthermore, bile duct ligation alone immediately declines the pressure in both sphincters. Vice versa, the esophagitis-sphincter failure procedure alone produced acute pancreatitis. What's more, these lesions (esophagitis, sphincter failure, acute pancreatitis when combined) aggravate each other (tubes into sphincters and ligated bile duct). Counteraction occurred by BPC 157 therapies. In acute pancreatitis patients lower pressure at rest was in both esophageal sphincters in acute pancreatitis patients. We conclude that BPC 157 could cure esophagitis/sphincter/acute pancreatitis healing failure.

Response of human HTB140 melanoma cells to conventional radiation and hadrons.

Conventional radiotherapy with X- and gamma-rays is one of the common and effective treatments of cancer. High energy hadrons, i.e., charged particles like protons and (12)C ions, due to their specific physics and radiobiological advantages are increasingly used. In this study, effectiveness of different radiation types is evaluated on the radio-resistant human HTB140 melanoma cells. The cells were irradiated with gamma-rays, the 62 MeV protons at the Bragg peak and in the middle of the spread-out Bragg peak (SOBP), as well as with the 62 MeV/u (12)C ions. The doses ranged from 2 to 24 Gy. Cell survival and proliferation were assessed 7 days after irradiation, whereas apoptosis was evaluated after 48 h. The acquired results confirmed the high radio-resistance of cells, showing better effectiveness of protons than gamma-rays. The best efficiency was obtained with (12)C ions due to higher linear energy transfer. All analyzed radiation qualities reduced cell proliferation. The highest proliferation was detected for (12)C ions because of their large killing capacity followed by small induction of reparable lesions. This enabled unharmed cells to preserve proliferative activity. Irradiations with protons and (12)C ions revealed similar moderate pro-apoptotic ability that is in agreement with the level of cellular radio-resistance.

Current thyroglobulin autoantibody (TgAb) assays often fail to detect interfering TgAb that can result in the reporting of falsely low/undetectable serum Tg IMA values for patients with differentiated thyroid cancer.

CONTEXT: Specimens have thyroglobulin antibody (TgAb) measured prior to thyroglobulin (Tg) testing because the qualitative TgAb status (positive or negative) determines risk for Tg assay interference, and the quantitative TgAb concentration serves as a surrogate tumor marker for differentiated thyroid cancer. OBJECTIVE: This study assessed the reliability of four TgAb methods to detect interfering TgAb [as judged from abnormally low Tg immunometric assay (IMA) to Tg RIA ratios] and determine whether between-method conversion factors might prevent a change in method from disrupting TgAb monitoring. METHODS: Sera from selected and unselected TgAb-negative and TgAb-positive differentiated thyroid cancer patients had serum Tg measured by both IMA and RIA and TgAb measured by a reference method and three additional methods. RESULTS: The Tg IMA and Tg RIA values were concordant when TgAb was absent. Tg IMA to Tg RIA ratios below 75% were considered to indicate TgAb interference. Manufacturer-recommended cutoffs were set in the detectable range, and when used to determine the presence of TgAb misclassified many specimens displaying Tg interference as TgAb negative. False-negative misclassifications were virtually eliminated for two of four methods by using the analytical sensitivity (AS) as the detection limit for TgAb. Relationships between values for different specimens were too variable to establish between-method conversion factors. CONCLUSIONS: Many specimens with interfering TgAb were misclassified as TgAb negative using manufacturer-recommended cutoffs. It is recommended that assay AS limits be used to detect TgAb to minimize false-negative misclassifications. However, for two of four assays, AS limits failed to detect interfering TgAb in 20-30% of cases. TgAb methods were too qualitatively and quantitatively variable to establish conversion factors that would allow a change in method without disrupting serial TgAb monitoring.

A simple method to assess freezing of gait in Parkinson's disease patients

Freezing of gait (FOG) can be assessed by clinical and instrumental methods. Clinical examination has the advantage of being available to most clinicians; however, it requires experience and may not reveal FOG even for cases confirmed by the medical history. Instrumental methods have an advantage in that they may be used for ambulatory monitoring. The aim of the present study was to describe and evaluate a new instrumental method based on a force sensitive resistor and Pearson's correlation coefficient (Pcc) for the assessment of FOG. Nine patients with Parkinson's disease in the "on" state walked through a corridor, passed through a doorway and made a U-turn. We analyzed 24 FOG episodes by computing the Pcc between one "regular/normal" step and the rest of the steps. The Pcc reached ±1 for "normal" locomotion, while correlation diminished due to the lack of periodicity during FOG episodes. Gait was assessed in parallel with video. FOG episodes determined from the video were all detected with the proposed method. The computed duration of the FOG episodes was compared with those estimated from the video. The method was sensitive to various types of freezing; although no differences due to different types of freezing were detected. The study showed that Pcc analysis permitted the computerized detection of FOG in a simple manner analogous to human visual judgment, and its automation may be useful in clinical practice to provide a record of the history of FOG.

A simple method to assess freezing of gait in Parkinson's disease patients.

Freezing of gait (FOG) can be assessed by clinical and instrumental methods. Clinical examination has the advantage of being available to most clinicians; however, it requires experience and may not reveal FOG even for cases confirmed by the medical history. Instrumental methods have an advantage in that they may be used for ambulatory monitoring. The aim of the present study was to describe and evaluate a new instrumental method based on a force sensitive resistor and Pearson's correlation coefficient (Pcc) for the assessment of FOG. Nine patients with Parkinson's disease in the "on" state walked through a corridor, passed through a doorway and made a U-turn. We analyzed 24 FOG episodes by computing the Pcc between one "regular/normal" step and the rest of the steps. The Pcc reached ±1 for "normal" locomotion, while correlation diminished due to the lack of periodicity during FOG episodes. Gait was assessed in parallel with video. FOG episodes determined from the video were all detected with the proposed method. The computed duration of the FOG episodes was compared with those estimated from the video. The method was sensitive to various types of freezing; although no differences due to different types of freezing were detected. The study showed that Pcc analysis permitted the computerized detection of FOG in a simple manner analogous to human visual judgment, and its automation may be useful in clinical practice to provide a record of the history of FOG.

Regional patterns of brain tissue loss associated with depression in Parkinson disease.

OBJECTIVE: To investigate, using MRI and voxel-based morphometry (VBM), whether specific patterns of gray matter (GM) and white matter (WM) loss are associated with depression in patients with Parkinson disease (PD). METHODS: Forty patients with PD and 26 healthy subjects were studied. Patients were diagnosed with depression using DSM-IV criteria. The Hamilton Depression Rating Scale (HDRS) was administered to patients. The topographic distribution of brain tissue loss in patients with PD and controls was assessed using VBM as implemented in Statistical Parametric Mapping (SPM5). RESULTS: Twenty-four patients with PD were diagnosed as nondepressed (PD-NDep) and 16 as having depression (PD-Dep). Patient groups were similar in terms of clinical findings, except for the HDRS score (p < 0.001). Compared to controls, patients with PD showed common GM loss in the right anterior cingulate (AC) cortex and insula, and in the left middle frontal and angular gyri (p < 0.001). No regions of WM loss common to PD-NDep and PD-Dep patients relative to healthy controls were found. PD-Dep vs PD-NDep patients showed WM loss in the right AC bundle and inferior orbitofrontal (OF) region (p < 0.001). In patients with PD, HDRS score correlated with WM loss in the right inferior OF region (r = -0.51, p < 0.05). CONCLUSIONS: Tissue loss in several WM regions within the cortical-limbic network occurs in PD-Dep vs PD-NDep patients. Such pattern of brain atrophy overlaps with key regions involved in major depressive disorders, suggesting an increased vulnerability of this neural circuit in PD. This may partially account for the high prevalence of depression in PD.

Insights into pathophysiology of punding reveal possible treatment strategies.

Punding is a stereotyped behavior characterized by an intense fascination with a complex, excessive, nongoal oriented, repetitive activity. Men tend to repetitively tinker with technical equipment such as radio sets, clocks, watches and car engines, the parts of which may be analyzed, arranged, sorted and cataloged but rarely put back together. Women, in contrast, incessantly sort through their handbags, tidy continuously, brush their hair or polish their nails. Punders are normally aware of the inapposite and obtuse nature of the behavior; however, despite the consequent self-injury, they do not stop such behavior. The most common causes of punding are dopaminergic replacement therapy in patients affected by Parkinson's disease (PD) and cocaine and amphetamine use in addicts. The vast majority of information about punding comes from PD cases. A critical review of these cases shows that almost all afflicted patients (90%) were on treatment with drugs acting mainly on dopamine receptors D1 and D2, whereas only three cases were reported in association with selective D2 and D3 agonists. Epidemiological considerations and available data from animal models suggest that punding, drug-induced stereotypies, addiction and dyskinesias all share a common pathophysiological process. Punding may be related to plastic changes in the ventral and dorsal striatal structures, including the nucleus accumbens, and linked to psychomotor stimulation and reward mechanisms. Possible management guidelines are proposed.

[Cardiac surgery in patients with heparin-induced thrombocytopenia (HIT II)].

Heparin-induced thrombocytopenia (HIT) might be life-threatening in patients undergoing open heart surgery, due to thromboembolic events, thrombocytopenia and bleeding. If cardiac surgery with cardiopulmonary bypass (CPB) is necessary, anticoagulation therapy will be based on usage of danaparoid or direct thrombin inhibitors. Female patient was switched from per oral anticoagulant therapy to low molecular heparin therapy preparing for reredo mitral valve replacement due to endocarditis and artificial valve thrombosis. In next 10 days, thrombocytopenia was obvious (Tr 302,000 mm3 to 11,000 mm3) , and diagnoses of HIT were done. Anticoagulant therapy was continued with danaparoid, 750 IU/12 h sc. During the surgery, reredo mitral valve replacement and aortocoronary bypass on anterior descending coronary artery, blood salvage technique with rhirudin (intravenous bolus 0.4 mg/kg, in CPB prajming solution 0.4 mg/kg and continuous infusion during CPB 0.15 mg/kg/h) during cardiopulmonary bypass was used. Active coagulation time and +++ were monitored, without any sign of micro thrombosis in circuit. Postoperatively, per oral anticoagulation therapy was initiated with prolonged postoperative treatment due to basic disease, endocarditis. Patient was discharged from hospital on 21st postoperative day without any complication.

Long-term outcome in Serbian patients with Wilson disease.

BACKGROUND AND PURPOSE: To investigate survival rates, prognostic factors, and causes of death in Wilson disease (WD). METHODS: In the years 1980-2007, a cohort of 142 patients with WD was prospectively registered (54 presented with neurologic symptoms, 49 with hepatic symptoms, 33 had mixed form, and data were missing for six patients). The duration of follow-up for patients alive was 11.1 +/- 8.8 years. RESULTS: After initiation of treatment (d-penicillamine and zinc salts), 79% of patients had a stable or improved course of disease. Despite early diagnosis and appropriate therapy, 15 patients still had a relentlessly progressive course. Thirty patients died. The cumulative probability of survival in a 15-year period for the whole group was 76.7 +/- 4.9%. Better prognosis of WD was associated with male sex, younger age at onset, neurologic form of the disease, and treatment continuity. Causes of death were predominantly related to hepatic failure (16 patients), but also suicide (four patients) and cancer (three patients). CONCLUSION: Despite the relatively early diagnosis and treatment of our patients with WD, mortality was still considerably high.

Early effects of gamma rays and protons on human melanoma cell viability and morphology.

The effects of irradiation with gamma rays and protons on HTB140 human melanoma cell morphology and viability were analyzed. Exponentially growing cells were irradiated close to the Bragg peak maximum of the 62-MeV proton beam, as well as with (60)Co gamma rays, with doses ranging from 8 to 24 Gy. The overall cell morphology was unchanged 6 and 48 h after gamma irradiation, also showing a relatively weak cell-inactivation level. After exposure to proton beam, considerable changes in cell morphology followed by stronger cell inactivation were achieved. Proliferation capacity of irradiated cells significantly decreased in both experimental set-ups. Higher ionization level of protons with respect to gamma rays, representing the main physical difference between these two types of radiation, was also revealed on the cell membrane level through larger pro-apoptotic capacity of protons.

Regression of nodular liver lesions in Wilson's disease.

Long-term follow-up abdominal imaging studies have not been reported previously in patients with the hepatic form of Wilson's disease (WD). This paper reports the case of a 35-year-old woman with symptoms dating back several months and with multiple, nodular liver lesions. The lesions were hyperdense on non-enhanced computed tomography and hypointense on T2-weighted magnetic resonance (MR) images. A diagnosis of WD was established several weeks after her admission to hospital, and chelating treatment was commenced promptly. No abnormalities were found on follow-up MR examinations of the abdomen and brain 4.5 years later. These imaging features suggest that so long as WD is diagnosed in the initial stages, liver nodules can regress with time and complete healing can be achieved with continuous decoppering treatment.

Galectin-3 and proliferating cell nuclear antigen (PCNA) expression in papillary thyroid carcinoma.

BACKGROUND AND AIM: To examine the relationship between galectin-3 and cell proliferation in thyroid tumor tissue. Galectin-3, a beta-galactoside binding protein, has recently been recognized as a promising molecular marker of thyroid malignancy, due to its high expression in thyroid carcinomas and absence from normal or benign thyroid tissue. However, its exact role in thyroid tumor biology is still unknown. PATIENTS AND METHODS: We examined the relationship between galectin-3 and cell proliferation by comparative immunostaining for galectin-3 and proliferating cell nuclear antigen (PCNA) in paraffin-embedded tissues from 126 cases of papillary thyroid carcinoma. RESULTS: Positive cytoplasmic immunostaining for galectin-3 was found in 115 (91.3%) cases. Nuclear staining for PCNA was detectable in 93 (74.4%) cases. A low level of PCNA staining (less than 10% positive cells) was found in 36 (28.6%) cases, moderate staining for PCNA (more than 10% but less than 30% positive cells) in 35 cases (27.8%), while highly increased PCNA expression (more than 30% positive cells) was found in 32 (25.4%) cases. Moderate or strong galectin-3 expression, found in 99 cases, was associated with highly increased PCNA staining in 28.3% of them but with no detectable PCNA expression in 24.3% of them. CONCLUSION: These results suggest that overexpression of galectin-3 is not clearly related to proliferative activity of papillary thyroid carcinoma cells as assessed by PCNA immunostaining.